Spiral traversal of matrix in php

Php program for Spiral traversal of matrix. Here problem description and other solutions.

<?php
// Php program for 
// Spiral form of matrix
class SpiralView
{
	public	function spiral($data, $startRow, 
                             $startCol, $endRow, 
                             $endCol, $element)
	{
		// Left to right
		for ($i = $startCol; $i <= $endCol && $element > 0; ++$i)
		{
			$element--;
			printf("%s", "  ".strval($data[$startRow][$i]));
		}
		// Top to down
		for ($i = $startRow + 1; $i <= $endRow && $element > 0; ++$i)
		{
			$element--;
			printf("%s", "  ".strval($data[$i][$endCol]));
		}
		// Bottom right to bottom-left
		for ($i = $endCol - 1; $i >= $startCol && $element > 0; --$i)
		{
			$element--;
			printf("%s", "  ".strval($data[$endRow][$i]));
		}
		// Bottom left to top
		for ($i = $endRow - 1; $i > $startRow && $element > 0; --$i)
		{
			$element--;
			printf("%s", "  ".strval($data[$i][$startRow]));
		}
		if ($startRow + 1 <= $endRow - 1 && $element > 0)
		{
			// Recursive call
			$this->spiral($data, $startRow + 1,
                          $startCol + 1, 
                          $endRow - 1, $endCol - 1, $element);
		}
	}
	public static
	function main($args)
	{
		$task = new SpiralView();
		// Given matrix
		$matrix = array(
          array(1, 2, 3, 4, 5, 6), 
          array(22, 23, 24, 25, 26, 7), 
          array(21, 36, 37, 38, 27, 8), 
          array(20, 35, 42, 39, 28, 9), 
          array(19, 34, 41, 40, 29, 10), 
          array(18, 33, 32, 31, 30, 11), 
          array(17, 16, 15, 14, 13, 12)
        );
		$row = count($matrix);
		$col = count($matrix[0]);
		// Get the number of element
		$element = $row * $col;
		$task->spiral($matrix, 0, 0, 
                      $row - 1, $col - 1, $element);
	}
}
SpiralView::main(array());

Output

  1  2  3  4  5  6  7  8  9  10  11  12  13  14  15  16  17  18  19  20  21  22  23  24  25  26  27  28  29  30  31  32  33  34  35  36  37  38  39  40  41  42